Abstract:
The present invention relates to a process for preparing an aromatic or heteroaromatic nitrile in the presence of a supported catalyst which comprises a support having a mean diameter of ≤ 78 µm. The present invention further relates to the novel supported catalyst as such and to a process for preparing this novel supported catalyst.
Abstract:
The invention relates to a method for producing 4-vinylcyclohexene comprising the following steps: (A) a feed gas stream containing n-butane is prepared; (B) said feed gas stream containing n-butane is fed to at least one dehydrogenation zone, where it is dehydrogenated from n-butane to butadiene, whereby a butadiene, n-butane, optionally 1-butene and 2-butene and optionally water vapour and a product stream containing additional minor constituents are obtained; (C) the product stream from the dehydrogenation, optionally after separation of the water vapour and minor constituents, is fed to a dimerization zone, where the butadiene is catalytically dimerized to obtain 4-vinylcyclohexene, n-butane and optionally 1-butene, 2-butene and a product stream containing butadiene that has not been converted; (D) the 4-vinylcyclohexene from the dimerization product stream is separated and the n-butane and optionally 1-butene, 2-butene and the butadiene that has not been converted are returned to the dehydrogenation zone.
Abstract:
Disclosed is a shell catalyst comprising: a) a supporting material selected among aluminum oxide, silicon dioxide, aluminum silicate, magnesium silicate, titanium dioxide, zirconium dioxide, thorium dioxide, silicon carbide, or mixtures thereof; and b) an active mass in the shell, containing vanadium (V), antimony (Sb), and at least one element selected among molybdenum (Mo) and/or tungsten (W) in an oxidic form, respectively. The supporting material is spherical or nearly spherical with a diameter ranging between 2 and 10 mm, or tubular. Also disclosed are a method for producing said shell catalyst as well as the use thereof in an ammoxidation process.
Abstract:
The present invention relates to a process for the preparation of particles comprising at least one compound according to general formula (I) M1aM2bM3cOoNnFf (I) wherein M1, M2, M3 O, N, F, a, b, c, o, n and f have the following meanings: M1 at least one alkaline metal, M2 at least one transition metal in oxidation state +2, M3 at least one non-metal chosen form S, Se, P, As, Si, Ge and/or B, O oxygen, N nitrogen, F fluorine, a 0.8-4.2, b 0.8-1.9, c 0.8-2.2, o 1.0-8.4, n 0-2.0 and f 0-2.0, wherein a, b, c, o, n and f are chosen to ensure electroneutrality of the compound according to general formula (I), and carbon, comprising at least the following steps: (A) providing an essentially aqueous mixture comprising at least one compound comprising M1, at least one compound comprising M2 having at least partially an oxidation state higher than +2, optionally at least one compound comprising M3, at least one compound comprising N, if present, and/or at least one compound comprising F, if present, at least one polysaccharide comprising glucose having a molecular weight M of at least 50000 g/mol as carbon precursor and at least one reducing agent, (B) drying the mixture provided in step (A), in order to obtain a solid particle and (C) calcining the solid particle obtained from step (B) at a temperature of 300 to 950° C.
Abstract:
The present invention relates to agglomerates made of at least one particle P, which is rendered hydrophobic at the surface using at least one first surface-active substance, and at least one magnetic particle MP, which is rendered hydrophobic at the surface using at least one second surface-active substance, to a method for the production thereof, and to the use of said agglomerates.
Abstract:
The invention relates to a method for converting a precatalyst which comprises a inert carrier, an organic carbon source and a silver and vanadium containing multimetal oxide to a gas phase oxidation catalyst comprising the inert carrier and a catalytically active silver-vanadium oxide bronze. According to said method, the precatalyst is thermally treated at a temperature of at least 350 °C in a gas atmosphere containing less than 10 % by volume of oxygen. Before the treatment, the carbon source quantity in the precatalyst is adjusted to a value below the critical quantity. The carbon quantity is reduced by separation at a temperature of 80 to 200 °C in an oxygen-containing atmosphere and concurrent decomposition of a portion of the carbon source. The catalysts so obtained are used for partial gas phase oxidation of aromatic hydrocarbons to aldehydes, carboxylic acids and/or carboxylic acid anhydrides.
Abstract:
The invention relates to a device and to a method for extracting non-magnetic ores from a pulp (P) comprising non-magnetic ore particles and having a solid fraction of at least 30 % mass. The pulp (P) flows through (100) a reactor (1) in the direction of flow.